HERV-K Env-induced lipid peroxidation was blocked by the endolysosome iron chelator deferoxamine in SH-SY5Y cells. For the determination of ferroptosis cell death, C11-BODIPY 581/591 was used as a measure of lipid peroxidation. A, Qualitatively, HERV-K Env (30 nM) increased lipid peroxidation fluorescence staining (green); these increases were blocked by pretreatment (1 h) with DFO (50 µM). B, Quantitatively, lipid peroxidation was significantly (p < 0.0001) increased by HERV-K Env (30 nM); these increases were blocked by pretreatment (1 h) with DFO (50 µM). An ANOVA with Tukey's post hoc multiple-comparisons test was used for analysis. Each data point represents the mean fluorescence of 30 cells performed independently five times for each group (n = 150). n = total number of cells for each group plotted. Cells were chosen randomly in the microscope's field of view and no cells were intentionally excluded. Scale bar = 20 µm. B, F_(3,16) = 32.2, p < 0.0001.